SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '4694bf37597151fa2a7c4768cd07b9c59272b0d652aa8e70748e6174efcad5d1' 
  AND token = 'vYveXf5Jcmb4XYKbaUqb5sfxZe84w2fUh6maNSfWFKc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00035

JSON explain

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