SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '54b5bd9e64fba2d63c4fc8885e02e5c0885448fc7b1a53f23cd6bec2185477b1' 
  AND token = 'YV0Fp5auuxTCSK5HyHSWsvm4fmB64Tql/KTQ6JJwGAk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00018

JSON explain

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