SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'ce6c707f29389ac0f58e2f14d01416f676e14accdfd1cba0037862345a3eae44' 
  AND token = 'L7RXErRYeJ0qQot/cnsvP6SMsjOPj30pay1t22e/OLI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00024

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}