SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '74ec7ec2566fe1c795eacfd3f1297d99e4ed7eed9416511efdfb623dbd796cf9' 
  AND token = '7QzZiFlNX8loqmJE1GeyYPkK8H9N3bkZboonDr8BkpM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00020

JSON explain

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