SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'ac644a29a5d1cf600102a9e63d878bdec0b391944fd0aad382fcefa825ea52d1' 
  AND token = '5nrbIo93sXmXeZUXNaTVfnBQqglgo8RCxNUp+GiqPww=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00049

JSON explain

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