SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '37e3cd79447495a57781d2371c9d425a91f364bfbb20bb83a9fb881029b471a0' 
  AND token = 'wHKOgtVPf6u1QgCanfs96BorTHsZzPri6UamGaUvqV8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00109

JSON explain

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