SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'd5deeaddc678397b5f1139dfbe0d33b57fb3d5fa29ead874f20fbd8d304e0de0' 
  AND token = 'hPIsbMhUN/8PKVVyZjoZCTc8rZC3NHFrt461FEP1H8M=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00036

JSON explain

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