SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '74742f1d20b4f457ae5e279115e0fed2d9694325c1a9387c8fe0a728f52befef' 
  AND token = 'Bteh2NxbQq+rPPDK19m5C+vrJd3YqIDg3+W/lmZuMyg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

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