SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '197491c736d51b60ccead3a5797fd124326173e2fe1026d793ff71a215fe6673' 
  AND token = 'bYhRiGd7bjepXlJn4w3SaIFHOL4gQD4l3avX4gBHoCQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00014

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}