SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '5ed6d1923ef67dcf44cef0db364b28ad9a7a6a02bd079ea32ec5edfd3e1e7033' 
  AND token = 'EpY/dr2yjYszjiAgSGzaL9WYpNoNlYfhSRp5LDQHbbc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

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