SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'bb6ba815fb4bee7a1754c9ea595593c47ba2f622a8fc1a9b62028fc039ab09e4' 
  AND token = 'dwdynY8pmYM6r6ImQpcNpapk+zmd3VG2aEp3XZIeThE=' 
  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"
    }
  }
}