SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '40c12a0c7ee8268558d1c45fa1853cec9855dec9ac105c0448dd7af9fb031f55' 
  AND token = 'FCQnvuUF32i7OI7siFqGylrJbAin6OvKEahAYM6fZ3w=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00041

JSON explain

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