SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '9e4dac73c3308131501c0deba5ff4fe7b8b7582fc5108f114b936efa8d2c863e' 
  AND token = 'XcDZcSNWJnSfA3Ddn5FWb5MKP/ebGAMBWojmcGzhIFo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00035

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}