SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'a0e385f941728cd29c3c57d35579b688c01cd16e24015a466813d5a6114bd6e6' 
  AND token = 'Ivy8iDDv9yig7+pi1NFYG1inAKfgBGH0qPMtO7G3RiQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00063

JSON explain

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