SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '2a3bc236eee4ec80ce2ef387bbe6d0b458861cc482053fc2976645f337171087' 
  AND token = 'ze2UewSibG6e/PChTKUM0U3/YJTiBtHDpXUktGDPJss=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

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