SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'd3d4e6f8f716968bdfdbef6272d363d1d1bc668ab44bf44343b9b59879ff057a' 
  AND token = 'gQqHsWKKtN82jvN+noYKlJL/EntyrZTcNZP2ppDU15U=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00078

JSON explain

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