SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'b2e31dd2c0346c1191a13ec9503850efbc248d3afe3a688aba7318156ae3510d' 
  AND token = 'idtuojh1D4guHY0v2sdQQl/ImxFgH+Ow7qHS6pZ5u2o=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00041

JSON explain

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