SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'deb81a9c45612e13e146a0de3f37f19b3c2052dd6025d906ac17a83993a6ef1b' 
  AND token = '8CIEHgJLRQmeuz5GkHY7SBF7y4P22Jo898sSjUUBlAU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00027

JSON explain

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