SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '4ac0aa0411bce613d78cf47a0c0e54d46301281562ddfe36b3abce254b19eb2e' 
  AND token = 'bLXPF9zit2xPHFebIiKJUrZUbh0abuQWOvYltp2Jdsk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00036

JSON explain

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