SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '0d1b052659954a17fa82c6da709f9ac70907953f43cf8f2159d8c75298661026' 
  AND token = 'F9bawB5paq4EmQbCnDqZsVb+Kh4fkE2z6ydQz5Z2jY4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00037

JSON explain

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