SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '734469cd0a8b1d5e7fa5146d0c096bff1290137667545376885113a212eae2b6' 
  AND token = 'ldqR+nNrOxjYlixHwBLPFvN0qvPEc5lSO4gk6ph3rGc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00021

JSON explain

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