SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'c16e7c36056c3ae927baae77486fcc939ad7437bd7e46aa73463058ea2f6a82a' 
  AND token = 'eFYrr0idA/cSbk9Fub4zBh1pA00LjK7GHu0OGIyCgek=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00021

JSON explain

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