SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '50e90695ab24a242e1e6c90561ff55ff83eaa79c8820b55d66701e89b2f3b672' 
  AND token = 'EYGOJtJchA7+lWDXtlzGUWZgvVlslsBGxtvAKQ8dclc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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