SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'ba891d4513ae2f85566891dddeb95f0963031f7f0e25dd792664cda51a7d83b9' 
  AND token = 'yD7myyazvhkgAgyuBFPf0KRgXhxNKohDXx0gScLPUH8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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