SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'c07e6e4083884b3e153832987096f4840ea66ca0995828124e4737b6335f5851' 
  AND token = 'o9pRX3TwZiR8t5/Ci4sRGDRoGAxHUnFXIayQWIc/foE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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