SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '9bbca80b722a804b60df492be16bec19f93af106b32ab2abbbd17f0388299f4b' 
  AND token = 'JIftomAPTnIMhG1ewWjvJH4tYmP1/R5qsb6pX1zzgwQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

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