SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'aded7a24eef77ffb453fc915f5ef1155177626f8cc36f8925eb82431cea703b3' 
  AND token = 'Dzst4wVSIgTNDyj+9SvVJTERcmc1QHUSW91w2ftHzg8=' 
  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"
    }
  }
}