SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '272326efd96fef9d883e23faf54afc5df74da7b828adc366203959a92022b32e' 
  AND token = 'DYY7ARBI5hazPqqZwitgHz9d+IsJ2npcmg4Mf52J/Js=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

JSON explain

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