SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'e75325d07dc50ca306ff27cf57f1f092ad52de892daa7b97deb7e917d4633cff' 
  AND token = 'J1uWGFLgQ+1lUd+vtTBCu5vhOUOdrydBRQMyVQYOnB0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00014

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}