SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '9ffb30406f01869b97dc01517da12b9f0eea03bf723aff502f3ef0c1d0d3b051' 
  AND token = '95yl/U4qJ5qCCpq3eyyOocVS22WludjvvL+FUf6fquc=' 
  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"
    }
  }
}