SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'af078923a95a7b6d8d055083cf36d35044656cbdb4a151f143d8c673921792e0' 
  AND token = 'JHLcuJfyfQ3vKc4OQwz8E/80AnPnnt1e2NAYtRBsXrc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00023

JSON explain

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