SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '4984a965983f0c8cd6b5f06c99fcc8d8fcd70520784a3531f2673f92afaa04d1' 
  AND token = 'o7+I8g8BTUu1hPRuXIXSqCGzijFwqQx192m1NLJoEn8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00042

JSON explain

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